A Motorized Clock

Made on a Glowforge
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I’ve wanted to make a clock since I first started dreaming of having my Glowforge, and finally the time has come for BETA 1.

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It’s made from paper and powered by 2 RPM engine (rotations per minute). So the first gear step is a 1:2 reduction making the first gear turn at the same pace as a seconds hand. I never added a hand to that though. The next several gears are there to reduce the rotation to that of the minute hand (rotates 1:60 compared to the second hand). Then another couple of complicated parts to make the second hand and minute hand to be co-axial.

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I used Fusion 360 to design it, and I used Matthias Wandels gear generator for the gears.

There were many prototypes along the way.

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What worked;
Using 2mm paper for a clock worked way better than I expected. The thing runs day in and and day out.

What didn’t work;
A 2 RPM motor does NOT turn 2 rotations per minute. I’m not sure how fast it turns, but the clock is off by half an our every day.

What comes next;
I’m getting a different motor - one that’s synchronized with the frequency of the power outlet, which should work much better.

And I’m remaking the entire thing out of really thin plywood. Probably not proofgrade, because that’s a bit too thick for my needs.

Let me know what you think!

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Very cool.

This belongs in the Made on a Glowforge gallery - would you mind if I moved it there?

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Quite the challenge! Nice work on a difficult idea.

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It used to be that only Proofgrade stuff was allowed there? Otherwise - it would be great if you moved it!

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Nice skills designing it yourself!

I would think that you need one that doesn’t sync with the power outlet frequency, unless the motor you have is 50 Hz and you are at 60 or vice versa. I am not electrical engineer, but frequency is nominal for the outlet supply, so having a standard frequency reference for your circuit is important.

We had some guys want to restore the giant 4 faced clock in our church bell tower. It had a cool central gearing mechanism that converted the one motor running at 60 cycles for all the movements. It hadn’t run for over thirty years. They got everything cleaned and aligned and back in action, including repainting the numbers. The thing doesn’t keep time well because the local power supply is so erratic.

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Yeah, it’s just the settings used that can’t be shared. Projects made (especially cool ones!) can be posted there.

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Anything made of a GF is allowed in “Made On A Glowforge” - the rule for “everything else” is that if you are sharing settings for non-proofgrade materials, the thread should be in Beyond the Manual (edited to correct my mistake.)

Amazing work you’ve done with this!

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You may be right, that it won’t be very accurate either, but it’ll be a lot more accurate than what I’ve got right now :wink: I’m getting a motor suitable for 50Hz at 230V, which is what we have here in Sweden.

Wiring 230V will be… interesting. I did study electrical engineering waaay back, so I have some notion of what I’m supposed to do…

Oh, one fun motor that’s easy to get is a microwave oven tray engine - they turn at a steady pace, but they go backwards every second startup. Imagine having to reboot your clock to make it go the right way. I’m tempted to get one just because. “Look, kids, looks we had a power outage, because the clock is running backwards!”.

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These days, your most accurate solution may be to look at an arduino-controlled stepper motor.

It’s a dirt cheap and stupidly over-complex, but highly-effective way to control a motor.

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Yes. They say that the clock that’s most often correct is the clock that’s stuck, because it’s EXACTLY right twice a day.

I say, one that runs backwards - REALLY QUICKLY - will be exactly accurate way more often that.

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I believe the cool factor of upcycling outweighs an accurate clock!

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Beyond the Manual is for funky settings :slight_smile:

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What I think is that this is excellent. Thanks for sharing.

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My mistake has been corrected… spaced it for a minute there… thanks.

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Then boy do I have the clock for you…

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There are dedicated clock motors that are highly regulated, might want to look for one of those. Something like this:

https://www.american-time.com/products-by-family/clock-parts-and-repairs/motors-movements

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Great work! Those gears look super!

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I do believe I am going to steal that one.
I will require adding - I Am Retired - to the phrase, though.
It just came out too great to only be a picture in my head.

disclaimer: might only go into the overly thick ‘some day’ file. We will see.

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When I used to be on FB, one of my friends, a retired school teacher, always posted about awful Mondays and how great Fridays were.

What?? I think they are doing it wrong!